Sealing section for a lamp

ABSTRACT

A sealing profile ( 4 ) serves to seal a casing ( 1 ) with respect to a cover disc ( 5 ) of a lamp ( 2 ). The sealing profile ( 4 ) is extruded from an elastomer and inserted into a groove ( 3 ), comprising a groove base ( 15 ), of the casing ( 1 ). The sealing profile ( 4 ) comprises a seal section ( 6 ) which comprises lateral contact surfaces ( 7,8 ) and interacts with the cover disc ( 5 ), a connection section ( 9 ) with a reduced cross-sectional surface and a foot section ( 10 ) with is provided with lateral retaining lips ( 11,12 ). The foot section ( 10 ) comprises a strip ( 16 ) which interacts in a sealing manner with the groove base ( 15 ). When the sealing profile ( 4 ) is in the relaxed state, the strip ( 16 ) is disposed entirely within a retaining groove ( 17 ) of the foot section ( 10 ). When inserting the sealing profile ( 4 ) into the groove ( 3 ) the retaining lips ( 11, 12 ) are pivoted towards and pressed against the ribs ( 25, 26 ) of the lateral surfaces ( 23, 24 ) of the connection section ( 9 ), wherein the strip ( 16 ) is pressed with a portion of its cross-sectional surface out of the retaining groove ( 17 ) into contact with the groove base ( 15 ).

[0001] The invention relates to a sealing profile according to the preamble of claim 1.

[0002] In the case of a known sealing profile of this type (DE 298 10 708 U1, FIG. 2) greater protection against moisture seeping in at the bottom of the groove is already achieved by a sealing rib at the foot section.

[0003] DE 42 05 442 A1 discloses the placement of a planar base surface of a sealing profile with its entire surface against a complementary planar base surface in the base of a receiving groove. This arrangement is still not able to prevent moisture from seeping in.

[0004] The object of the invention is to prevent in a reliable manner moisture seeping in at the base of the groove.

[0005] This object is achieved by virtue of the features of claim 1. The strip prevents any penetration of moisture between the sealing profile and the base of the groove. A preferred area of application is the sealing of motor vehicle headlamps, where the cover disc can be made from synthetic material or glass and where it is imperative that the sealing effect is always guaranteed even during changes in temperature and vibrations.

[0006] In accordance with claim 2 the strip is also held in the retaining groove in a reliable manner even when the sealing profile is in the relaxed state.

[0007] The features of claim 3 serve to guarantee the adhesive characteristics of the strip even until the sealing profile is inserted into the groove.

[0008] According to claim 4 the strip can be protected in this manner even without a cover sheet until it is inserted in the groove.

[0009] The features of claim 5 further enhance this protective effect.

[0010] According to claim 6 during the process of inserting the sealing pro-file into the groove the cross-sectional shape of the retaining groove can be changed in a convenient manner as desired.

[0011] The features of claim 7 facilitate the process of pressing the strip out of the retaining groove.

[0012] According to claim 8 it is possible to control in an extremely precise manner the process of pressing out the strip and to influence said process.

[0013] The features of claim 9 enhance the pressing-out effect, wherein the mass of the strip can spread out in the desired manner and to the desired extent between the groove base and the inserted sealing profile and a sufficiently permanent sealing effect can be ensured.

[0014] According to claim 10 the strip is held in a particularly reliable manner in situ in the foot section.

[0015] The features of each of claims 11 to 13 ensure a permanent, complete moisture seal at the base of the groove.

[0016] The features of claim 14 provide a particularly favourable sealing effect on the one hand within the groove and on the other hand between the seal section and the cover disc.

[0017] Further features and advantages of the invention are evident from the following description of the exemplified embodiments illustrated in the drawings, in which:

[0018]FIG. 1 is a cross-section through a sealing profile inserted into a groove of a casing, the sealing profile is however illustrated in the relaxed starting position, and

[0019]FIG. 2 is a cross-sectional view according to FIG. 1 through a different embodiment of the sealing profile.

[0020]FIG. 1 illustrates a part of a casing 1 of a lamp 2 of a motor vehicle. A sealing profile 4 is inserted in a groove 3 of the casing 1. The sealing profile 4 comprises a seal section 6 which has lateral contact surfaces 7 and 8 and interacts with a cover disc 5 of the lamp 2, the said contact surfaces lying against the lateral surfaces, the upper lateral surfaces in FIG. 1, of the groove 3 when the sealing profile 4 is inserted in the groove 3 prestressed in a transverse manner. The seal section 6 in FIG. 1 becomes in the downward direction a connection section 9 which has a reduced cross-sectional surface. The connection section 9 provides an elastic connection to a foot section 10 which is provided with opposing lateral retaining lips 11 and 12. When the sealing profile 4 is pressed into the groove 3 the retaining lips 11, 12 move inwards into the channels 13 and 14 between the groove 3 and the connection section 9. As a consequence on the one hand a good sealing effect of the sealing profile 4 to the side is achieved with respect to the lateral walls of the groove 3 and on the other hand a considerable amount of static friction is achieved which prevents the sealing profile 4 from falling out unintentionally from the groove 3, whilst the cover disc 5 is not fixed in position.

[0021] The foot section 10 comprises facing a groove base 15 of the groove 3 a strip 16 which interacts in a sealing manner with the groove base 15. The strip 16 is disposed with a portion of its cross-sectional surface in a retaining groove 17 of the foot section 10. Preferably, the strip consists of a permanently adhering, butyl-based sealing mass. Until the sealing profile 4 is inserted into the groove 3, the surface portion of the strip 16 protruding out of the retaining groove 17 can be covered by a cover sheet [not illustrated].

[0022] As the sealing profile 4 is pressed into the groove 3 the strip 16 comes into contact with the groove base 15 and becomes connected in a permanently adhering and elastic manner to the groove base 15. In this manner moisture which has still penetrated between the seal section 6 and a lateral wall of the groove 3 is prevented from penetrating between the groove base 15 and the strip 16.

[0023] Referring to FIG. 2, like parts are identified by like reference numerals in FIG. 1.

[0024] The exemplified embodiment according to FIG. 2 is similar to that in accordance with FIG. 1. However, the retaining lips 11, 12 in FIG. 2 in the illustrated relaxed position of the sealing profile 4 are somewhat longer and placed in a flatter manner than in FIG. 1. The retaining groove 17 is defined in FIG. 2 partially by inner ends 18 and 19 of the retaining lips 11, 12. In the case of a relaxed sealing profile, as illustrated in FIG. 2, the inner ends 18, 19 form a gap 20 between themselves.

[0025] In the case of a relaxed sealing profile 4 the strip 16 is disposed entirely within the retaining groove 17 and in fact at a spaced disposition 21 from the outer contour 22 of the foot section 10. Thus, a free, in FIG. 2 bottom, surface of the strip 16 therefore lies protected within the retaining groove 17. As a consequence, it is not necessary to cover this free surface by a cover sheet until the sealing profile 4 is inserted in the groove 3.

[0026] As the sealing profile 4 is inserted into the groove 3 the retaining lips 11, 12 are pivoted upwards, moved into the channels 13, 14 and pressed against the lateral surfaces 23 and 24 of the connection section 9. As a consequence, on the one hand the gap 20 is enlarged and on the other hand the strip 16 is pressed with one portion of its cross-sectional surface out of the retaining groove 17 into sealing contact with the groove base 15.

[0027] In order to promote this pressing-out effect, each lateral surface 23, 24 can be provided with a rib 25 and 26 respectively which protrudes outwards towards the associated retaining lip 11, 12. These ribs 25, 26 are preferably disposed in the region of the, in FIG. 2 upper, end of the retaining groove 17, so that the pressing-out effect, starting from this upper end of the retaining groove 17, progresses to its lower end. 

1. Sealing profile (4) for sealing a casing (1) with respect to a cover disc (5) of a lamp (2), wherein the sealing profile (4) can be extruded from at least one elastomer and can be inserted into a groove (3), comprising a groove base (15), of the casing (1), wherein the sealing profile (4) comprises a seal section (6) which has lateral contact surfaces (7,8) and interacts with the cover disc (5), a connection section (9) which has a reduced cross-sectional surface and a foot section (10) which is provided with lateral retaining lips (11,12), characterised in that facing the groove base (15) of the groove (3) the foot section (10) comprises a strip (16) which interacts in a sealing manner with the groove base (15).
 2. Sealing profile in accordance with claim 1, characterised in that the strip (16) is disposed with a portion of its cross-sectional surface in a retaining groove (17) of the foot section (10) when the sealing profile (4) is in the relaxed state and not yet inserted into the groove (3).
 3. Sealing profile in accordance with claim 2, characterised in that until the strip (16) is inserted into the groove (3) the strip is covered by a cover sheet along a surface region protruding out of the groove (3).
 4. Sealing profile according to claim 1, characterised in that the strip (16) is disposed entirely within a retaining groove (17) of the foot section (10) when the sealing profile (4) is in the relaxed state and not yet inserted into the groove (3).
 5. Sealing profile in accordance with claim 4, characterised in that the strip (16) is disposed at a spaced disposition (21) from an outer contour (22) of the relaxed foot section (10).
 6. Sealing profile in accordance with any one of claims 2 to 5, characterised in that the retaining groove (17) is defined partially by inner ends (18,19) of the retaining lips (11,12).
 7. Sealing profile in accordance with claim 6, characterised in that when the sealing profile (4) is in the relaxed state the inner ends (18, 19) form a gap (20) between themselves.
 8. Sealing profile in accordance with claim 7, characterised in that when inserting the sealing profile (4) into the groove (3) the retaining lips (11,12) can be pivoted towards and pressed against the lateral surfaces (23, 24) of the connection section (9), and that as a consequence on the one hand the gap (20) can be enlarged and on the other hand the strip (16) can be pressed out of the retaining groove (17) with a portion of its cross-sectional surface into contact with the groove base (15).
 9. Sealing profile in accordance with claim 8, characterised in that in order to promote the pressing-out effect each lateral surface (23,24) is provided with a rib (25, 26) which protrudes outwards towards the associated holding lip (11,12).
 10. Sealing profile in accordance with any one of claims 1 to 9, characterised in that the strip (16) is disposed with a portion of its cross-sectional surface in a retaining groove (17) of the foot section (10), when the sealing profile (4) is inserted into the groove (3).
 11. Sealing profile in accordance with any one of claims 1 to 10, characterised in that the strip (16) consists of a permanently elastic sealing mass.
 12. Sealing profile in accordance with any one of claims 1 to 11, characterised in that the strip (16) consists of a permanently adhering sealing mass.
 13. Sealing profile in accordance with any one of claims 1 to 12, characterised in that the strip (16) consists of a butyl-based sealing mass.
 14. Sealing profile in accordance with any one of claims 1 to 13, characterised in that the sealing profile (4) consists of an EPDM cellular rubber having a Shore A hardness of 15 to
 25. 